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Journal of Cleaner Production 87 (2015) 675e682

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Journal of Cleaner Production

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Government initiatives

Substitution of hazardous offshore chemicals in UK waters: anevaluation of their use and discharge from 2000 to 2012

Maximillian A.G. La V�edrine*, David A. Sheahan*, Rosalinda Gioia, Bob Rowles,Silke Kroeger, Claire Phillips, Mark F. KirbyCentre for Environmental Fisheries and Aquaculture Science, Lowestoft Laboratory, Pakefield Road, Lowestoft, Suffolk NR33 0HT, United Kingdom

a r t i c l e i n f o

Article history:Received 7 June 2014Received in revised form12 September 2014Accepted 15 September 2014Available online 7 October 2014

Keywords:Chemical substitutionOffshore oil and gasOSPARChemical management

* Corresponding authors.E-mail addresses: max.lavedrine@cefas.co.uk (

sheahan@cefas.co.uk (D.A. Sheahan).

http://dx.doi.org/10.1016/j.jclepro.2014.09.0530959-6526/Crown Copyright © 2014 Published by Els

a b s t r a c t

The offshore oil and gas industry will use and discharge large quantities of chemicals into the marineenvironment during operational activities, with some of those chemicals considered hazardous. Chem-ical substitution, as part of the environmental regulatory regime, has been advocated as a simple andeffective tool to reduce inputs of hazardous substances to the environment. In 2007 the UK National Planwas introduced, to prioritise into four groups and subsequently phase out in stages the most hazardoussubstances used and discharged during offshore oil and gas operations. Level 1 substances categorisedfor phase out in 2010 were virtually eliminated from discharge between 2006 and 2012 and there was asignificant decline in discharge of substances at Level 2 to 4 over the same period. The discharge ofsubstitutable substances had been reduced to less than 5 tonnes at most production installations by2012. More than 91% of this discharge is contributed by corrosion inhibitor, scale inhibitor, demulsifierand water clarifier formulations. The discharge of corrosion inhibitors accounted for the largest contri-bution to UK National Plan Level 2 substitutable substance discharges, and they appear to be the type ofproduct with the fewest options found for substitution. This implies that a finite discharge of substancesfrom these groups will continue to require formal justification beyond the target date, as occurred forLevel 1 substances after the 2010 target date. The overall figures for substitutable substance dischargesfrom 2006 to 2012 suggest that the introduction of the UK National plan with prioritisation of substancesfor substitution and ongoing encouragement of operators and, indirectly, suppliers to work towardsreduction goals for substitutable substances is resulting in a reduction in discharges and contributing totheir ultimate phase out. The next few years will be particularly challenging as the deadline for thephase-out of discharges of substitutable substances included in OSPAR Recommendation, 2006/3 is 1January 2017 and, in addition, by 2018 all chemical substances used offshore will need to have beenregistered under the EC REACH Regulation. The approach described in this paper illustrates the benefitsof a prioritised strategy for chemical substitution and an ongoing dialogue between the industry andregulator. A continuing case by case dialogue with offshore operators and suppliers will be essential toensure that alternative technical solutions are trialled and options for substitution are investigated at theearliest stage.Crown Copyright © 2014 Published by Elsevier Ltd. This is an open access article under the CC BY license

(http://creativecommons.org/licenses/by/3.0/).

1. Introduction

The amount of man-made chemical substances increasedenormously during the twentieth century, with the total globalproduction of chemicals growing from 1 million tonnes/year in1930 to 500 million tonnes/year in 2005 (The Danish Ecological

M.A.G. La V�edrine), dave.

evier Ltd. This is an open access a

Council, 2006). There are chemicals that are known to possesshazardous properties and to present human and environmentalhealth risks, whilst the hazards and risks posed by many othershave never been assessed (The Danish Ecological Council, 2006).The most common legislative approach to elimination of the use ofhazardous substances is the substitution principle (Hansson et al.,2011). Although several definitions of the principle exist in envi-ronmental legislation (Lofstedt, 2013) for the purposes of this re-view it will be regarded as ‘the substitution of hazardoussubstances by less hazardous, or preferably non-hazardous, alter-natives where such alternatives are available’ (European

rticle under the CC BY license (http://creativecommons.org/licenses/by/3.0/).

Table 1UK National Plan level criteria and interim target dates.

UK nationalplan level

Ecotoxicological properties Phase out date

Level 1 Organic substances that are highlypersistent, bioaccumulating and toxic

End December 2010

Level 2 Organic substances that are: moderatelypersistent, bioaccumulating and toxic;or highly persistent and bioaccumulating;or highly persistent and toxic

End December 2012

Level 3 Organic substances that are: moderatelypersistent and bioaccumulating;or moderately persistent and toxic;or bioaccumulating and toxic

End December 2014

Level 4 Organic substances that are highlypersistent; or inorganic substanceswith toxicity <1 mg/l

End December 2016

M.A.G. La V�edrine et al. / Journal of Cleaner Production 87 (2015) 675e682676

Commission, 2001). The basis of this definition is the hazardassociated with each substance, which is related to its inherentproperties.

Methods used to promote substitution on the basis of chemicalhazard have been highlighted in various documents (Hansson et al.,2011; Lohse and Lißner, 2003). These include bans, lists of un-wanted chemicals, positive lists and substitution plans (Hanssonet al., 2011). Examples of lists of unwanted and dangerous sub-stances are the OSPAR List of Chemicals for Priority Action (LCPA),OSPAR List of Substances of Possible Concern (LSPC), REACH Sub-stances of Very High Concern (SVHC) and the Directive 2013/39/EUpriority substance list. Positive lists of acceptable substances, orsubstance group/classes, include the OSPAR Pose Little Or No Risk(PLONOR) to the environment list, the REACH Annex IV list and theSwedish BASTA system.

The substitution principle is most often applied on the basis ofhazard (Hansson et al., 2011; Lofstedt, 2013) but it is noted thatalternative approaches exist based on risk, which in addition tothe inherent properties take into account public and environ-mental exposure to the substance, in part determined by usage. Ithas also been proposed that, although it is possible to rankchemicals in order of their hazard properties, a risk-basedapproach is more appropriate in order to select a safer alterna-tive (UK Royal Society of Chemistry, 2007, Hansson et al., 2011 andLofstedt, 2013). Hansson et al. (2011), stated that all decisions onchemical substitutions should be based on the best available evi-dence, and it is generally accepted that the evidence can be suf-ficient to warrant a substitution even if it only consists of hazardinformation and it is not possible to undertake quantitative riskestimates.

This review focuses on chemicals used in offshore oil and gasexploration on the UK continental shelf (UKCS) and the trends inthe use and discharge of hazardous substances by this sector. TheUKCS has been exploited for hydrocarbons for over 40 years, duringwhich time more than 3300 million tonnes of oil and 2,600,000million cubic metres of gas have been produced (DECC UK monthlyproduction data). The extraction of these reserves has requiredconsiderable use of chemicals, both during the exploration phase,primarily related to the use of complex drilling fluids, and duringthe subsequent production phase, where chemicals are required toassist gas, condensate, oil and water separation, to protect equip-ment from corrosion and to ensure safety. After use, many of thesechemicals are discharged into the sea, creating a potential risk tothe marine environment.

In the UK, the risks from such activities are controlled throughthe Offshore Chemical Regulations 2002 (as amended) which arebased upon internationally-agreed principles set out in OSPARDecision, 2000/2 (as amended by OSPAR Decision, 2005/1) on aharmonised mandatory control system for the use and reduction ofthe discharge of offshore chemicals (HMCS). The regulations areadministered and enforced by the Department of Energy andClimate Change (DECC) and require operators to perform an envi-ronmental risk assessment of the use and discharge of chemicals aspart of a permit application process.

In order to obtain a permit, the operator must select onlychemicals that have been registered and their hazards assessed byCefas (the Centre for Environment, Fisheries and Aquaculture Sci-ence), acting on behalf of DECC. One of the key components in theregistration process is pre-screening, and it is at this stage thatsubstances that are candidates for substitution, i.e. substitutablesubstances (SSs), are identified. The pre-screening is conductedaccording to OSPAR Recommendation 2010/4, which examineschemicals based upon the persistence, bioaccumulation potentialand toxicity (PBT) of their component substances. Those chemicalsthat contain components qualifying as particularly hazardous are

identified as SSs and are flagged in the lists of registered substanceswith a substitution warning.

In 2006, OSPAR Recommendation, 2006/3 invited ContractingParties to develop National Plans to establish a time frame for thepotential cessation of the discharge of SSs from offshore in-stallations. In response, the United Kingdom National Plan (UKNP)was developed and published in 2007.

The essential elements of the UKNP are summarised in Table 1.Under the plan, chemical products (formulations consisting ofmany substances or composed of a single substance) are assignedto one of four levels 1e4, with level 1 denoting the highest priorityfor substitution. Where a product contains multiple SSs of differingUKNP levels, the product is assigned the UKNP level of its highestpriority component substance. All four levels were assigned a rec-ommended phase-out target, which was 2010 for UKNP level 1substances, and extended to 2016 for UKNP level 4 substances.

Presented here are the results from a study which examinedchanges in the use and discharge of SSs, and the substitutableproducts (SPs) containing them, during UKCS offshore oil and gasproduction operations between 2000 and 2012. This time frameincludes the ten years that followed the introduction of theOffshore Chemicals Regulations, and the period immediately beforethat introduction, and the six years that followed the imple-mentation of OSPAR Recommendation, 2006/3. Temporal andspatial trends of SSs and SPs are discussed, and their causes ana-lysed. Finally, the future outlook for substitution is considered.

2. Methods

The chemical usage and discharge data was collated in twostages; the first stage conducted in 2006 collated data for the years2000e2005 prior to the formation of the UKNP levels. The secondstage conducted in 2013 collated data for the years 2006e2012. Themethod used to obtain data at both stages was the same, themethod below outlines how the data was collated for 2006 to 2012.

Data was collated from the Environmental Emissions Moni-toring System (EEMS) returns submitted by offshore operators.EEMS is the environmental database maintained by DECC for theUK oil and gas industry that provides measured and calculated datarelating to emissions (including discharges to sea) from offshoreinstallations and some associated onshore terminals (Oil and Gas:EEMS database). The reported year, product names, registrationnumbers, installation names and reported use and discharge datain EEMS were imported into a Microsoft Access database that waslinked to a live copy of the offshore chemical registration databasemaintained by Cefas, and the EEMS data was analysed using in-formation on the products and substances (e.g. PBT data, CASnumbers, and product function) held on the Cefas database. For the

Fig. 1. Total use and discharge of offshore chemicals between 2000 and 2012.

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purpose of this review the components of the offshore chemicalproducts were separated into three groups: PLONOR, substitutableand non-substitutable.

A database query run on the 16th October 2013 returned in-formation on the composition of offshore chemical products,including the product function; product substitution warning sta-tus; product UKNP level; component substances, percentagecomposition data; substance substitution warning status; andsubstance UKNP level for the years 2006e2012. This ‘snapshot’ ofinformation on chemical composition and current substitutionstatus was compared to data for the years 2000e2005, since it isnot uncommon for chemical registration information and substi-tution status to change over time due to the availability of addi-tional data being submitted by the chemical manufacture or supplycompany. For 2006e2012 the substitution status of the chemicalwas classified based on the data available on 16th October 2013, inorder to ensure consistency over this period.

Where appropriate, trends in the data thus obtained were thensubjected to statistical analysis, and a linear model for analysis ofcovariance was used to evaluate the relationship between dis-charges against time. Details of the statistical analysis are providedin the Supplementary Data appended to this paper.

It should be noted that the data used for this study concernschemicals that have been used and discharged during productionoperations only, since these are responsible for most of the dis-charges of SSs. Chemicals are also discharged in the course of otheroffshore activities (e.g. drilling operations, well intervention/work-over/abandonment operations, pipeline operations and decom-missioning operations) but these are not included. Drilling dis-charges generally comprise relatively benign chemicals (Sheahanet al., 2007), whilst the quantities of SSs involved in the other op-erations are small by comparison.

3. Results and discussion

3.1. Temporal trends in the use and discharge of offshore chemicals2000e2012

Between 2000 and 2012 overall UK oil production fell (DECCMonthly Oil Production Data), as a result of production declinefrom ageing reservoirs and an increase in the number of uneco-nomic fields that had ceased production, which was exacerbated byextended shutdowns for repair of the infrastructure used by fieldsthat are still operational.

Although these factors contribute to reduced chemical use, theyare balanced by the fact that chemical use increases as exploitedfields age (Igunnu and George, 2013) and new fields were devel-oped during the period. The net effect is that chemical use anddischarge cannot be predicted from the production figures. Theoverall pattern of use and discharge of offshore chemicals between2000 and 2012 is shown in Fig. 1, indicating that after peaking in2005, the quantity of chemicals discharged during 2012 was similarto that recorded for 2000, at 26,899 and 28,817 tonnes respectively.

Fig. 2A shows the annual quantities of substances discharged ineach of the three groups (defined in Section 2) between 2000 and2012. The most notable trend is the decline of SSs discharged,which fell from a total of ~2700 tonnes in 2000 to <800 tonnes in2012: less than half of the initial quantity. Most of the decline isobserved between 2006 and 2012, with the total decreasingsteadily by a total of 1664 tonnes, despite a 6 tonne increase in2010. A clear decrease in the proportion of the total that is consti-tuted by SSs is also apparent, with SSs represented around 10.2% ofthe total of all substances discharged in 2000 and ~2.8% in 2012,whilst the discharge of the non-substitutable substances andPLONOR remained fairly constant over time. The net result has been

an overall shift in chemical discharge in favour of less hazardoussubstances, and this is further emphasised by Fig. 2B, which showsthe extent to which the proportion of SSs in the overall tonnage hasfallen between 2000 and 2012.

Further analysis of the data is presented in Fig. 3, which showsthe trends in the discharges of SPs (Fig. 3A) and SSs (Fig. 3B) be-tween 2006 and 2012, broken down by UKNP level (this analysis isnot possible for products registered before 2006, when the use ofsubstance-level data for chemical registration became mandatory).The linear model for analysis of covariance indicated that thedecline of discharges versus time is statistically significant with 95%confidence for UKNP levels 2, 3 and 4. There was no statisticalsignificance for UKNP level 1 products and substances from 2006 to2012, but the discharge of these substances had already beenvirtually eliminated.

Whilst the observed reductions are a welcome trend, it doeshowever indicate that the complete elimination of discharges fromUKNP levels 2, 3 and 4 is unlikely to materialise before the relevanttargets proposed by DECC, which fall outside the period covered bythis review. This implies that a finite discharge of substances fromthese groups will continue to require formal justification beyondthe target date, as occurred for UKNP level 1 substances after the2010 target date. In the case of those substances, the small quan-tities discharged (<1 tonne on average) reflected isolated instanceswhere the need for a product featuring such substances had beenjustified by the operator and permitted by DECC. It should also benoted that, in 2011, the discharge of only one UKNP level 1 productwas permitted, at a single installation, and no discharges wererecorded for 2012.

3.2. Spatial distribution of the use and discharge of substitutablesubstances and products

The location and total amount of SSs discharged at offshore oiland gas installations on the UKCS are shown in Fig. 4. Comparisonof the data between 2006 and 2012 illustrates where significantreductions in SS discharges have occurred during that period. Sig-nificant improvements are indicated for the most northerly in-stallations, but no other regional trends are apparent. The majorityof installations (74%) discharged less than 5 tonnes of SSs in 2012.Most installations which discharged 25e75 tonnes and >75 tonnesof SSs in 2006 had reduced their discharges to less than 25 tonnesin 2012 and, at some installations, to less than 5 tonnes in 2012.Fig. 4 shows there were six instances of SS discharges of >75 tonnesin 2006, and only one in 2012.

Fig. 4 also indicates that the installations that discharge themost SSs are generally located in the northern North Sea, whilst the

Fig. 2. Top Figure: Discharges of PLONOR, substitutable and non substitutable substances present in production chemicals between 2000 and 2012. Bottom Figure: Discharges ofsubstitutable substances as a percentage of the total discharge.

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installations in the southern North Sea discharge much smallerquantities. This regional trend reflects the prevalence of gasextraction activities in the southern North Sea, which are relativelyundemanding in terms of chemical requirements compared withoil extraction activities. Thus, installations in areas off the east coastof Scotland and Shetland, in the central and northern North Sea,involved in both oil and gas extraction, have higher discharges ofSSs and SPs. These discharges often relate to the use of inhibitors forwaxes and asphaltenes, as the deposit of these substances wouldreduce the efficiency of the extraction of the crude oil.

3.3. Chemical functions of substitutable products

Between 2000 and 2012 over a million tonnes of products(substitutable, non-substitutable and PLONOR) were used as part ofoffshore oil, condensate and gas production operations. Between2006and2012 the total amountusedwas541,442 tonneswith by farthe largest contributor being 155,758 tonnes of gas hydrate in-hibitors (Figure S1 in the Supplementary data). However, althoughgas hydrate inhibitors accounted for more than a quarter of theentire tonnage of chemical products used between 2006 and 2012,

gas hydrate inhibitors are generally relatively low-risk chemicals(e.g. alcohols) and the total use of these inhibitors only contributedto less than 10 kg of SS discharge during the same period.

The next most widely-used chemicals comprise scale inhibitors(62,473 tonnes), hydrogen sulphide scavengers (59,599 tonnes) andcorrosion inhibitors (52,185 tonnes), all contributing over 10% ofthe total tonnage used between 2006 and 2012 and contributing tothe amount of SSs discharged during the same period. However, asindicated in Fig. 5, the extent of the contribution to the discharge,and the associated trends, differ significantly for the three chemicalfunction groups. In the case of hydrogen sulphide scavengers, SSsrepresent only a small, and declining, proportion of the total dis-charged. In the case of scale inhibitors, SSs are markedly moreabundant, and as a result this chemical function group wasresponsible for the greatest discharge of SSs in 2006. However, thedischarge of scale inhibitors has decreased steadily since 2006 andthis chemical function group was only the fourth largest contrib-utor to SSs discharge in 2012. In contrast, SSs discharges attribut-able to corrosion inhibitors have remained fairly constant since2007, and this chemical function group is now the most significantsource of such discharges.

Fig. 3. Total discharges (tonnes) of products containing substitutable substances (A) and substitutable substances (B) at different UK National Plan Levels discharged offshorebetween 2006 and 2012.

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To function effectively, corrosion inhibitors must provide aprotective layer separating a metal surface from the liquid (usuallywater) with which it is in contact. In order to create such a barrier,the corrosion inhibitor molecule must offer both a polar group thatwill adhere to the metal and a hydrophobic group (typically a hy-drocarbon chain, or “tail”) that will prevent penetration by water.This requirement dictates the need for a surfactant component and,unless the surfactant has a molecular weight of >700, thiscomponent will be deemed to be potentially bioaccumulative in theabsence of suitable data (Dugue et al., 2011). Since metallic surfacestend to acquire a negative charge whenwet (Lomax, 1998), cationictypes are most effective, such as imidazolines and quaternaryammonium salts, but cationic surfactants are generally toxic (Lewiset al., 1991). The combination of toxicity and bioaccumulation po-tential therefore results in a substitution warning. The creation ofenvironmentally friendly corrosion inhibitors is thus seen to beproblematic, since the very properties that they require to performtheir function will also qualify them as SSs under the OSPAR Pre-

screening scheme. The chemical industry is nevertheless devotingconsiderable effort to tackle this challenge, for example one studyhas explored the optimisation of the length of the alkyl ethoxylatesof some corrosion inhibitor molecules, since shorter alkyl chains ofthe ethoxylated propoxylated polymer offer lower toxicity whilstlonger alkyl chains provide better corrosion protection (Donaldsonet al., 2011). Another study has considered the potential for poly-meric corrosion inhibitors (Hellberg, 2013). However, such de-velopments have yet to have a significant impact in terms ofoffshore use.

3.4. The UK substitution strategy the future development ofsubstitution in the UK

Although many studies have identified legislation as one ofthe most powerful drivers for chemical substitution (Reibstein,2008; Verschoor and Reijnders, 2001), others have shown thatenvironmental legislation alone is not always sufficient to ensure

Fig. 4. The location and total amount of substitutable substance discharge in 2006 (left) and 2012 (right) and a comparison of UK National Plan level substitutable substancedischarge in 2006 (bottom left) and 2012 (bottom right). Each dot represents an installation.

M.A.G. La V�edrine et al. / Journal of Cleaner Production 87 (2015) 675e682680

that future reduction targets are met, and greater levels ofinnovation across the chemical supply industry are needed torealise further progress (Lofstedt, 2013). However, chemicalsubstitution is rarely a simple process, and when a substitution ismade without an understanding of all the issues involved this hasthe potential to increase rather than decrease risks (Laden andGray, 1993; Tickner et al., 2013). The potential to increase risksis due to the multifaceted nature of chemical substitution,

Fig. 5. Total substitutable substance discharged by function type between 2006 and 2012 (pincluded).

encompassing acute or chronic health risks, safety and fire risks,the limited knowledge of the toxicity of chemicals (Gray, 1995),the error associated with incorrect available information(Verschoor and Reijnders, 1998), the possible shift in risks whenconsidering different types of environments (i.e. workplaceversus marine or terrestrial environment) (Goldschmidt, 1993;Hoet et al., 1997; Rossi et al., 1991) and the possible shift inrisks in relation to specific use scenarios.

roduct function types with total substitutable discharge of less than 50 tonnes are not

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The introduction of the UKNP has established recommendedpriorities for substitution but, in view of the issues outlined above,the UK accepts that the replacement of SPs may prove to be atechnically or financially unsustainable option in some cases.Where this applies, the UKNP allows offshore operators tocontinue to formally justify the proposed use and discharge ofchemicals that are candidates for substitution. Operators aretherefore required to compile technical justification documents,which summarise i) the use and/or discharge of the chemical, ii)the reasons why it is necessary to use and/or discharge thechemical, iii) the efforts made to phase out the use or discharge ofthe chemical, and iv) the reasons why phase out of use ordischarge is not currently considered to be feasible (i.e. technicalor/and safety reasons). Although it is therefore possible for oper-ators to continue to use and discharge SSs beyond the targetdeadline, a strong incentive is maintained favouring the replace-ment of the relevant products.

Looking ahead, the next decade will be one of considerablechallenge to industry and regulators alike. The deadline for thephase-out of discharges of SSs included in OSPAR Recommenda-tion, 2006/3 is 1 January 2017 and, in addition, by 2018 all chemicalsubstances used offshore will need to have been registered underthe EC REACH Regulation, which presents its own SS definitionsand protocols that differ in detail from those currently employed byOSPAR. Whilst OSPAR is committed to the harmonisation of itsregulatory framework with that of REACH where possible andwhere it does not dilute the OSPAR regime, significant obstaclesneed to be overcome before this can be fully achieved. EU MemberStates will also be striving to demonstrate compliance with theMarine Strategy Framework Directive, and its associated target ofachieving Good Environmental Status by 2020. How these regula-tory demandswill be reconciled with the continuing demand for oiland gas remains to be seen.

4. Conclusions

Although the quantity of chemical substances dischargedfrom offshore oil and gas production installations did notdecrease greatly between 2000 and 2012, the nature of thechemicals discharged shifted towards those of a less hazardousnature. In particular, the proportion of the total comprising of SSsfell significantly during the period 2000-2012 with the mostnortherly installations showing notable reductions between2006 and 2012. These outcomes provide evidence that theOffshore Chemical Regulations, introduced in 2002, and the UKNational Plan, introduced in 2007, have been effective in pro-moting the use of less hazardous substances, and that thestrategy adopted towards discouraging the discharge of SSs hasbeen successful. However, significant progress remains to bemade before the unnecessary discharge of such substances canbe eliminated, and fundamental technical obstacles will need tobe overcome. Although the discharge of UK National Plan level 1substances fell to zero in 2012, current trends indicate that SSs atother levels will continue to be discharged beyond the phase-outdates outlined in the UK National Plan, and the industry willneed to continue to justify those discharges to the regulatoryauthorities.

The approach described in this paper illustrates the benefitsof a prioritised strategy for chemical substitution and an ongoingdialogue between the industry and regulator. A continuing caseby case dialogue with offshore operators and suppliers will beessential to ensure that alternative technical solutions are tri-alled and options for substitution are investigated at the earlieststage.

Acknowledgements

The authors would like to express their deepest appreciation toDerek Saward and Mark Shields of DECC Oil and Gas and the OCNSteam at Cefas Lowestoft for their professional and efficient work inrelation to the risk assessment of offshore chemicals. In particularwe would like to thank Lynn G. Jones, Steve Supple, Cheryl Moranand Linda M. Hughes for their invaluable help and support with theoffshore work.

Acronyms

CAS Chemical Abstracts ServiceCefas Centre for Environment, Fisheries and Aquaculture

ScienceDECC Department of Energy and Climate ChangeEC European CommissionEEMS Environmental Emissions Monitoring SystemHMCS Harmonised Mandatory Control SchemeLCPA List of Chemicals for Priority ActionLSPC List of Substances of Possible ConcernOCNS Offshore Chemical Notification SchemeOSPAR Oslo and Paris Conventions: The Convention for the

Protection of the Marine Environment of the North-EastAtlantic

PBT Persistence, Bioaccumulation and ToxicityPLONOR Pose Little or No RiskREACH Registration, Evaluation, Authorisation and Restriction of

ChemicalsSPs Substitutable ProductsSSs Substitutable SubstancesSVHC Substances of Very High ConcernUK United KingdomUKCS United Kingdom Continental ShelfUKNP United Kingdom National Plan

Appendix A. Supplementary data

Supplementary data related to this article can be found at http://dx.doi.org/10.1016/j.jclepro.2014.09.053.

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